LOS ANGELES (AP) — Michael Jackson’s doctor was not qualified to treat the singer for insomnia or drug addiction and botched resuscitation efforts, an expert cardiologist testifying for the singer’s mother told a jury on Tuesday.

Dr. Daniel Wohlgelernter said he reached his conclusion after reviewing the credentials of Conrad Murray, who was later convicted of involuntary manslaughter in Jackson’s 2009 death.

Wohlgelernter testified during a lawsuit filed by Katherine Jackson claiming Murray was negligently hired by concert promoter AEG Live LLC to care for the pop star.

Attorneys for both sides told the panel last week that Michael Jackson suffered from longstanding prescription drug addiction issues.

Wohlgelernter said Murray had no formal training on how to treat such problems, and the former cardiologist was not qualified to administer propofol, the powerful anesthetic that killed Jackson. The singer was using the drug as a sleep aid.

Wohlgelernter, a Santa Monica-based cardiologist, also told the jury that Murray improperly focused on Jackson’s heart when the singer stopped breathing after receiving propofol and other drugs on June 25, 2009.

Jackson’s mother claims in the lawsuit that AEG failed to properly investigate Murray or his finances. AEG denies wrongdoing and says it was Michael Jackson who wanted Murray to work as his doctor while he prepared for a series of comeback shows.

Murray had been expecting to receive $150,000 a month for his work on Jackson’s tour, but the singer died before the contract was finalized.

Under cross-examination by AEG attorney Kathryn Cahan, Wohlgelernter testified that Murray’s training and credentials were reputable and he appeared to be a competent internal medicine physician.

Wohlgelernter, however, said Jackson’s request for Murray to be his doctor and Murray’s desire to leave other patients behind to work with the singer should have caused AEG some concern.

Wohlgelernter said the company should have asked why the two men wanted to work with each other.

Several other doctors testified during Murray’s 2011 criminal trial that the doctor repeatedly violated the standard of care in his treatments on Jackson.